Why a standard method overlooks the real reason some antibiotics fail

Antibiotics show limited effectiveness against Salmonella bacteria in infected mice. Conventional methods of analysing bacterial growth suggest that a small subset of hyper-resilient bacteria is the main cause of this poor efficacy. However, direct monitoring of antibiotic action in real time reveals that such methods are misleading, and that Salmonella resilience is a population-wide trait. Real-time imaging shows that bacterial resilience to antibiotics is not caused by a few ‘persisters’, but is a population-wide trait.